Fumarase Deficiency

Fumarase deficiency is an inherited condition that affects the brain and other parts of the nervous system. Signs and symptoms may include a small head (microcephaly), severe developmental delay, poor feeding, weak muscle tone (hypotonia), failure to thrive, seizures, and distinctive facial features. Most people with this deficiency are not able to speak or walk. A variety of brain abnormalities may be detected on MRI. Fumarase deficiency is caused by mutations in the FH gene and inheritance is autosomal recessive. Unfortunately, there is no effective treatment at this time. Management aims to improve symptoms and increase quality of life. Many children with fumarase deficiency do not survive past early childhood, but some are less severely affected, have mild cognitive impairment, and survive beyond this time.